This invention relates generally to a germicide and, more specifically, to a germicidal composition suitable for preventing growth of various germs such as yeasts and filamentous fungi in industrial water such as waste water from pulp mills or cooling water for heat exchangers.
In industrial water such as waste water from paper making steps in pulp-related industries and recirculating cooling water used in various mills, microorganisms such as germs, fungi and bacteria are apt to grow and to cause various problems.
For example, filamentous fungi and yeasts are apt to grow in industrial water used in paper or pulp mills and to form slime within water passages such as pipe walls having roughened surfaces and other portions such as chests and flow boxes through which the water is passed at a low flow rate. The accumulated slimes occasionally depart from their depositing surfaces to cause contamination of paper and pulp products. Other industrial products such as aqueous coating materials, polymer latex, bonding agents, metal machining oils, hides and skins also encounter similar problems. Further, accumulation of slimes also cause blockage of water passages and reduction of heat transfer efficiency.
To cope with these problems, there have been hitherto used organometallic compounds, chlorinated organic compounds, sulfur-containing organic compounds and quarternary ammonium compounds for the prevention of growth of germs in industrial water. These known germicides, however, have certain problems. That is, the known organometallic compounds and chlorinated organic compounds must be used in a large amount in order to obtain satisfactory germicidal effects. This causes environmental pollution. The known sulfur-containing organic compounds and quarternary ammonium compounds cause a problem of generation of unpleasant odor. Some of these compounds also cause a problem of foaming of the water to which they are added.
Japanese Examined Patent Publication (Tokkyo Kokoku) No. Sho-51-33,171 discloses a germicide containing an .alpha.-chlorobenzaldoxime acetate derivative of the general formula (I): ##STR3## wherein n is an integer of 0 to 2. Japanese Tokkyo Kokoku No. 43-16460 discloses a germicide containing 2-bromo-2-nitro 1,3-diacetyloxypropane of the formula (II): ##STR4## These germicides are effective only against limited kinds of germs and lack durability in germicidal effect.